package demo02;

import java.util.Scanner;

/*题目：编写一个函数，输入n为偶数时，调用函数求1/2+1/4+...+1/n,当输入n为奇数时，调
用函数1/1+1/3+...+1/n(利用指针函数)*/
public class topic39 {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        System.out.println("请输入n的值");
        int n=scanner.nextInt();
        System.out.print(sum(n));
    }
    public static double sum(int n){
        double sum=0;
        if(n%2==0){
            for (int i = 2; i <=n; i+=2) {
                sum+=1.0/i;
                if(i!=n){
                    System.out.print(1+"/"+i+"+");
                }else{
                    System.out.print(1+"/"+i+"=");
                }

            }
        }else{
            for (int i = 1; i <=n; i+=2) {
                sum+=1.0/i;
                if(i!=n){
                    System.out.print(1+"/"+i+"+");
                }else{
                    System.out.print(1+"/"+i+"=");
                }
            }
        }
        return sum;
    }
}
